Vertical luminophore particle tracer profiles expressed as relative counts for replicate macrofaunal communities from the Western Barents Sea in summer 2017 and 2018

Software: ImageJ (version 1.47s),Data were collected from each of 5 stations in 2017 (B13-B17) and 6 stations in 2018 (B13-B17 and Xs) during two consecutive cruises (RRS James Clark Ross: JR16006, 30th June to 8th August, 2017; JR17007: 10th July to 5th August, 2018) following a transect along the 30&deg;E meridian. At each station four replicate intact sediment cores (LWH: 20 x 20 x 12 cm) were obtained from replicate 0.1m2 USNL (Unites States Naval Laboratory) box cores using a core extruder, transferred to transparent acrylic aquaria (internal dimensions, LWH: 20 x 20 x 34 cm) and overlain with ~8 L (20cm depth) surface seawater (salinity, ~34). Aquaria (2017, n = 20; 2018, n = 24) were randomly transferred to one of two insulated fibreglass seawater baths (LWH: 1.2 x 1.2 x 0.8m, Tanks Direct, UK) and maintained at a representative ambient bottom temperature in the dark. Faunal mediated sediment particle reworking was estimated by establishing the redistribution of optically distinct particulate tracers (luminophores: 215g aquaria-1, fluorescent green, </span

Sediment particle size analysis for stations from the Western Barents Sea for summer 2017 and 2018

Sediment particle size frequency distributions from the USNL (Unites States Naval Laboratory) box cores were determined optically using a Malvern Mastersizer 2000 He-Ne LASER diffraction sizer and were used to resolve mean particle size, sorting, skewness and kurtosis. Samples were collected on cruises JR16006 and JR17007. Funding was provided by &#39;The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems&#39; project (NE/N015894/1 and NE/P006426/1, 2017-2021), part of the NERC funded Changing Arctic Ocean programme.,Data were collected from each of 5 stations in 2017 (B13-B17) and 6 stations in 2018 (B13-B17 and Xs) during two consecutive cruises (RRS James Clark Ross: JR16006, 30th June to 8th August, 2017; JR17007: 10th July to 5th August, 2018) following a transect along the 30&deg;E meridian. At each station, sediment samples were obtained from four replicate 0.1m2 USNL (Unites States Naval Laboratory) box cores and analysed using a Malvern Mastersizer 2000 He-Ne LASER diffraction sizer for sediment particle size at the University of Cambridge following a standard protocol (provided). Resolution: Laster particle analysis range 0.03-2000 &micro;m.</span

Experimental measurements for replicate macrofaunal communities from the Western Barents Sea for summer 2017 and 2018

Standard protocols were followed and data entry double checked by independent person.,Measurements of benthic invertebrate particle reworking, bioirrigation, and associated nutrient concentrations used in the analyses by Solan et al. 2020 (Philosophical Transactions of the Royal Society A) for shipboard incubations of replicate macrofaunal communities from the Western Barents Sea during summer 2017 and summer 2018. Data were collected on cruises JR16006 and JR17007. Funding was provided by &#39;The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems&#39; project (NE/N015894/1 and NE/P006426/1, 2017-2021), part of the NERC funded Changing Arctic Ocean programme.,Data were collected from each of 5 stations in 2017 (B13-B17) and 6 stations in 2018 (B13-B17 and Xs) during two consecutive cruises (RRS James Clark Ross: JR16006, 30th June to 8th August, 2017; JR17007: 10th July to 5th August, 2018) following a transect along the 30&deg;E meridian. At each station four replicate intact sediment cores (LWH: 20 x 20 x 12 cm) were obtained from replicate 0.1m2 USNL (Unites States Naval Laboratory) box cores using a core extruder, transferred to transparent acrylic aquaria (internal dimensions, LWH: 20 x 20 x 34 cm) and overlain with ~8 L (20cm depth) surface seawater (salinity, ~34). Aquaria (2017, n = 20; 2018, n = 24) were randomly transferred to one of two insulated fibreglass seawater baths (LWH: 1.2 x 1.2 x 0.8m, Tanks Direct, UK) and maintained at a representative ambient bottom temperature in the dark. Faunal mediated sediment particle reworking metrics were estimated after 12 days by establishing the redistribution of optically distinct particulate tracers (luminophores: 215g aquaria-1, fluorescent green, </span

Fluorescent sediment profile images (fSPI) for replicate macrofaunal communities from the Western Barents Sea for summer 2017 and 2018

Images of the macrofaunal mediated redistribution of optically distinct particulate tracers (luminophores) for intact communities from the western Barents Sea after 12 days incubation. Images of all four sides of each aquarium are taken using a digital SLR camera housed within a UV illuminated imaging box. Data were collected on cruises JR16006 and JR17007. Funding was provided by &#39;The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems&#39; project (NE/N015894/1 and NE/P006426/1, 2017-2021), part of the NERC funded Changing Arctic Ocean programme.,Data were collected from each of 5 stations in 2017 (B13-B17) and 6 stations in 2018 (B13-B17 and Xs) during two consecutive cruises (RRS James Clark Ross: JR16006, 30th June to 8th August, 2017; JR17007: 10th July to 5th August, 2018) following a transect along the 30&deg;E meridian. At each station four replicate intact sediment cores (LWH: 20 x 20 x 12 cm) were obtained from replicate 0.1m2 USNL (Unites States Naval Laboratory) box cores using a core extruder, transferred to transparent acrylic aquaria (internal dimensions, LWH: 20 x 20 x 34 cm) and overlain with ~8 L (20cm depth) surface seawater (salinity, ~34). Aquaria (2017, n = 20; 2018, n = 24) were randomly transferred to one of two insulated fibreglass seawater baths (LWH: 1.2 x 1.2 x 0.8m, Tanks Direct, UK) and maintained at a representative ambient bottom temperature in the dark. Faunal mediated sediment particle reworking was estimated by establishing the redistribution of optically distinct particulate tracers (luminophores: 215g aquaria-1, fluorescent green, </span

Sediment surface images (SSI) for replicate macrofaunal communities from the Western Barents Sea for summer 2018

Original unedited images provided.,Images of the macrofaunal mediated redistribution of optically distinct particulate tracers (luminophores) for intact communities from the western Barents Sea after 12 days incubation. Images taken from above each aquarium using a digital SLR camera. Data were collected on the cruise JR17007. Funding was provided by &#39;The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems&#39;&#39;&#39; project (NE/N015894/1 and NE/P006426/1, 2017-2021), part of the NERC funded Changing Arctic Ocean programme.,Data were collected from each of 6 stations in 2018 (B13-B17 and Xs) during research cruise (RRS James Clark Ross: JR17007 (10th July to 5th August, 2018) following a transect along the 30&deg;E meridian. At each station four replicate intact sediment cores (LWH: 20 x 20 x 12 cm) were obtained from replicate 0.1m2 USNL (Unites States Naval Laboratory) box cores using a core extruder, transferred to transparent acrylic aquaria (internal dimensions, LWH: 20 x 20 x 34 cm) and overlain with ~8 L (20cm depth) surface seawater (salinity, ~34). Aquaria (n = 24) were randomly transferred to one of two insulated fibreglass seawater baths (LWH: 1.2 x 1.2 x 0.8m, Tanks Direct, UK) and maintained at a representative ambient bottom temperature in the dark. Faunal mediated sediment particle reworking was estimated by establishing the redistribution of optically distinct particulate tracers (luminophores: 215g aquaria-1, fluorescent green, </span

Macrofaunal abundance and biomass for replicate macrofaunal communities from the Western Barents Sea for summer 2017 and 2018

Sediment cores were taken using a box corer. The sediment was subsampled using a 20 x 20 x 12 cm and incubated for 12 days. At the end of incubation, the macrofauna retained (500 um sieved) from each aquarium were fixed in 10% phosphate buffered formalin (4% formaldehyde) and stored in sealed plastic buckets for a minimum of three months. Prior to identification samples were rinsed and preserved in 70% industrial methylated spirit (IMS). Using a stereo microscope, all the animals were picked out of the residue, stored in vials containing 70% IMS, and identified to the lowest possible taxon with abundance and biomass per taxon noted. Biomass was obtained using blotted wet weight (+/- 0.0001g). The individual numbers of each taxa were counted to give abundance data. This was determined by the presence of a head in cases where specimens had been damaged. Any badly damaged specimens or parts of specimens where no head was present were separated into major group debris (annelid, mollusc and crustacea) pots and their presence noted as YES/NO for abundance). All molluscs were weighed inclusive of shells, tube dwelling polychaetes were weighed without tubes, and sediment was removed from the body cavity of specimens of Ctenodiscus crispatus prior to weighing. Samples were collected on cruises JR16006 and JR17007. Funding was provided by &#39;The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems&#39; project (NE/N015894/1 and NE/P006426/1, 2017-2021), part of the NERC funded Changing Arctic Ocean programme.,All data was input by 2 people and double checked at input. Biomass data was checked against the abundance data to ensure cells with values corresponded between the 2 files. Species names were checked against accepted names at http://www.marinespecies.org/. Faunal identification was independently quality assured by C. Louise McNeill and Tom Mesher (Plymouth Marine Laboratory).,Data were collected from each of 5 stations in 2017 (B13-B17) and 6 stations in 2018 (B13-B17 and Xs) during two consecutive cruises (RRS James Clark Ross: JR16006, 30th June to 8th August, 2017; JR17007: 10th July to 5th August, 2018) following a transect along the 30&deg;E meridian. At each station four replicate intact sediment cores (LWH: 20 x 20 x 12 cm) were obtained from replicate 0.1m2 USNL (Unites States Naval Laboratory) box cores using a core extruder, transferred to transparent acrylic aquaria (internal dimensions, LWH: 20 x 20 x 34 cm) and overlain with ~8 L (20cm depth) surface seawater (salinity, ~34). Aquaria (2017, n = 20; 2018, n = 24) were randomly transferred to one of two insulated fibreglass seawater baths (LWH: 1.2 x 1.2 x 0.8m, Tanks Direct, UK) and maintained at a representative ambient bottom temperature in the dark. At the end of incubation, the macrofauna retained (500 &micro;m sieved) from each aquarium were fixed in 10% phosphate buffered formalin (4% formaldehyde) and stored in sealed plastic buckets for a minimum of three months. Prior to identification samples were rinsed and preserved in 70% industrial methylated spirit (IMS). Using a stereo microscope, all the animals were picked out of the residue, stored in vials containing 70% IMS, and identified to the lowest possible taxon with abundance and biomass per taxon noted. Biomass was obtained using blotted wet weight (&plusmn; 0.0001g). The individual numbers of each taxa were counted to give abundance data. This was determined by the presence of a head in cases where specimens had been damaged. Any badly damaged specimens or parts of specimens where no head was present were separated into major group debris (annelid, mollusc and crustacea) pots and their presence noted as YES/NO for abundance). All molluscs were weighed inclusive of shells, tube dwelling polychaetes were weighed without tubes, and sediment was removed from the body cavity of specimens of Ctenodiscus crispatus prior to weighing. Resolution: A total of 2550 faunal individuals representing 153 taxa were recovered from stations B13-B17, with 1353 individuals (22.8602 g biomass) representing 123 taxa in 2017 and 1197 individuals (15.8390g biomass) representing 113 taxa in 2018. An additional 403 individuals (4.3943g biomass), representing 45 taxa, were recovered from station Xs in 2018. A total of 157 unique taxa (63% identified to species level, 92% to genus level; 2953 individuals, 43.0935g biomass), were recovered across all stations and both years. All data are values per aquarium.</span

Sediment organic material by loss on ignition for stations from the Western Barents Sea for summer 2017 and 2018

Sediment organic material content obtained from replicate 0.1m2 USNL (Unites States Naval Laboratory) box cores are determined by loss on ignition. Samples were collected on cruises JR16006 and JR17007. Funding was provided by &#39;The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems&#39; project (NE/N015894/1 and NE/P006426/1, 2017-2021), part of the NERC funded Changing Arctic Ocean programme.,Data were collected from each of 5 stations in 2017 (B13-B17) and 6 stations in 2018 (B13-B17 and Xs) during two consecutive cruises (RRS James Clark Ross: JR16006, 30th June to 8th August, 2017; JR17007: 10th July to 5th August, 2018) following a transect along the 30&deg;E meridian. At each station, sediment samples were obtained from four replicate 0.1m2 USNL (Unites States Naval Laboratory) box cores and analysed for sediment organic material content (%) at the University of Cambridge following a standard protocol (provided). Sediment weighted to 3 decimal places.</span

High-resolution three-dimensional images of deep-sea bamboo corals Acanella arbuscula and Keratoisis sp. collected in the Baffin Bay and Davis Strait during the CCGS Amundsen expedition in 2021

Nikon XT custom designed micro-focus computed tomography system (based on the XT H 225 ST, Nikon Tring, UK) Remotely operated submersible (Sub-Atlantic Comanche, Forum Energy TechnologiesTM, USA) WaterPikTM (Johannes &amp;amp; Wiebe 1970) CT Pro software (6.6/6.7; Nikon Xtek, Tring UK) Fiji/ImageJ software (v 1.53c; Schindelin et al., 2012),High-resolution X-ray computed tomography images of two deep-sea bamboo corals (Acanella arbuscula, Johnson, 1862; Keratoisis sp., Wright, 1869) collected from Baffin Bay and Davis Strait during a research expedition on board the CCGS Amundsen in July-August 2021. Corals were imaged using Micro-Focused X-Ray Computed Tomography at the Micro-Vis X-ray Imaging Centre (Southampton, UK) to non-destructively investigate their skeletal architecture, calcification strategies and growth patterns. Supported by a National Environmental Research Council Funded (INSPIRE) PhD [grant number NE/S007210/1, 2019-2027, awarded to T.J.W] and the National Research Facility for Lab X-ray CT (NXCT) [EPSRC grant number EP/T02593X/1].,Five specimens of Acanella arbuscula and four specimens of Keratoisis sp. were collected from two stations (Davis Strait; 63.34533 degrees N; 58.19571 degrees W, 1311 m, 29th July 2021, Disko Fan; 67.96631 degrees N, 59.49381 degrees W, 889 m, 2nd August 2021) using a remotely operated submersible (Sub-Atlantic&micro; Comanche, Forum Energy TechnologiesTM, USA) during the 2021 Amundsen expedition (AMD21 Leg 2; 15th July 2021 - 12th August 2021, CCGS Amundsen). Where possible, corals were sampled at or close to the basal internode (near the base of the specimen at the sediment surface). Any external debris and residing fauna were carefully removed from the collected colonies using tweezers before each specimen was sealed in a plastic Ziplock bag and frozen at -20 degrees Celsius. After 72 hours, the specimens were removed from the freezer and carefully cleaned with jets of re-circulated 0.45 micrometer membrane-filtered seawater (FSW) at 4 degrees Celsius using a WaterPikTM (Johannes &amp;amp; Wiebe 1970) before being placed back in -20 degrees Celsius. The cleaned skeleton portions were then sealed in new Ziplock plastic sample bags enclosed in Tupperware (Acanella arbuscula) or PVC vinyl tubing (Keratoisis sp.) before being transported to the University of Southampton, UK. Reconstruction of biogenic structures was achieved using a Nikon XT custom designed micro-focus computed tomography system (based on the XT H 225 ST, Nikon Tring, UK) housed within the 3D X-ray Histology (XRH) facility (www.muvis.org). Coral specimens were securely positioned vertically in Perspex holding tubes with polystyrene bungs to ensure stability during rotation and scanning. Scans were conducted at 80 KVp using a Molybdenum target. Lower resolution scans (50 micrometer) used a 12 W power, while higher resolution scans (15 micrometer) reduced it to 6.9 W for a sharper X-ray focal spot. A water tube was also scanned under the same conditions as the samples to serve as a density reference. CT Pro 3D 6.6 or 6.7 software (Nikon Xtek, Tring UK) was used for all reconstructions. Due to the limited scanner field of view, multiple overlapping scan positions were used and merged after reconstruction to remove cone beam artifacts. This merging process was facilitated by a custom macro in Fiji, allowing alignment of the scans based on the same slice. The script could also adjust image contrast to compensate for any heel effect in the absence of density calibration. The final 32-bit volume was converted to an 8-bit volume using Fiji/ImageJ (v 1.53c; Schindelin, Arganda-Carreras, Frise et al., 2012) and then converted to stacked tagged image file format (TIFF) images to reduce data size and facilitate further processing. More detailed methodology surrounding sampling and scanning can be found in Williams, Standish, Archambault et al. [in prep] and Williams, Katsamenis, Basford, et al. [in prep], respectively.,Coral specimens were securely positioned vertically in Perspex holding tubes with polystyrene bungs to ensure stability during rotation and scanning. A water tube was also scanned under the same conditions as the samples to serve as a density reference. CT Pro 3D 6.6 or 6.7 software (Nikon Xtek, Tring UK) was used for all reconstructions. During concatenation of separate scans, image contrast was adjusted to compensate for any heel effect in the absence of density calibration. Conversion to stacked tagged image file format (TIFF) images was lossless.</span

Dissolved nutrient and particulate material concentrations and phytoplankton abundance and community composition from cruise JC211 to South Georgia, Southern Ocean, February 2021

Marine macronutrient and particulate material concentrations together with phytoplankton abundance and community composition were measured from samples taken during British Antarctic Survey and UK National Oceanography Centre research cruise JC211 to the Scotia Sea, Southern Ocean, carried out onboard RRS James Cook in February-March 2021. Samples were taken from four sections of the cruise: (i) at the British Antarctic Survey Scotia Sea Open-Ocean Observatory (SCOOBIES) P3 mooring in the Georgia Basin, northwest of South Georgia; (ii) as part of the British Antarctic Survey long-term Polar Ocean Ecosystem Time Series - Western Core Box (POETS-WCB) survey at South Georgia; (iii) in the vicinity of giant iceberg A-68A and associated icebergs; and (iv) as part of the A23 repeat hydrographic section. Samples were collected to maximum depth of approximately 500 m from Niskin water bottles attached to a CTD rosette. Full data analyses were performed post-cruise. Concurrent temperature, salinity, dissolved oxygen, chlorophyll fluorescence and photosynthetically active radiation (PAR) measurements obtained from analysis of water samples and from sensors on the CTD system at the depth and time of each water sample are provided for environmental context. RRS James Cook cruise JC211 was in part supported by the Natural Environment Research Council (NERC) National Capability Science (Antarctic Logistics and Infrastructure; NC-ALI) programme. Further funding for sampling around iceberg A-68 was provided by the Government of South Georgia and the South Sandwich Islands and the UK Government Blue Belt Programme. Data acquisition and analyses were supported by NERC NC-ALI funding to the Ecosystems CONSEC Programme and NERC Grants NE/N018095/1 (ORCHESTRA) and NE/V013254/1 (ENCORE) at the British Antarctic Survey, and by the European Research Council (ERC Starting Grant 678371 ICY-LAB to K Hendry) and NERC Grant NE/K010034/1 (to SF Henley)